Environmental Degradation as a Global Trend

First and most important in the early modern era [1450–1750 C.E.] is the intensified human land use in every world region. Rising human numbers put increasing pressure on the land. Almost invariably [human] expansion caused a reduction in the quantity and diversity of vegetation or, to put it in other terms, a reduction in biomass and biodiversity. That is, sedentary cultivation depended on selection of one or a few favored plant species...in place of a variety of grass, shrubs, and trees.... Agriculture was and continues to be the single most important means by which humans change the world’s lands and its ecosystems.